CVE-2021-22600
HighExploitedPublic exploitA double free bug in packet_set_ring() in net/packet/af_packet.c can be exploited by a local user through crafted syscalls to escalate privileges or deny service.
Published Jan 26, 2022 · Updated Oct 14, 2026 · Also known as A-213464034, ASB-A-213464034, DEBIAN-CVE-2021-22600, PUB-A-213464034, SUSE-SU-2022:0365-1, SUSE-SU-2022:0544-1, UBUNTU-CVE-2021-22600, USN-5266-1, USN-5294-1, USN-5294-2, USN-5295-1, USN-5295-2, USN-5298-1
Key Facts
Patch immediately- CVE-2021-22600 is a high-severity vulnerability (CVSS 7.0 v3.1) affecting Debian Linux, Linux Kernel, 8300 Firmware (Netapp) and 22 more products.
- It is exploited in the wild, listed in CISA KEV, Industry KEV feed, CIRCL KEV, ENISA EUVD since Mar 7, 2022. Public exploit code is available.
- EPSS estimates a 6.6% probability of exploitation in the next 30 days.
- Fixed versions are available, including :linux_kernel: :2022-03-05, :linux_kernel: :2022-05-05, bpftool 5.10.46-2.ph4.
- Brandefense priority: patch immediately, because it is listed as exploited in the wild.
CVSS v3.1
7.0
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS (30-day exploit likelihood)
6.6%
Higher than 93.7% of all scored CVEs
Exploited in the wild
Yes
4 catalog listings
Public exploit code
Available
Proof-of-concept or weaponized module
Get the full CVE-2021-22600 brief as a PDF
Every affected product and fixed release, exploitation status and a first 24 hours response checklist, emailed within minutes.
Description
A double free bug in packet_set_ring() in net/packet/af_packet.c can be exploited by a local user through crafted syscalls to escalate privileges or deny service. We recommend upgrading kernel past the effected versions or rebuilding past ec6af094ea28f0f2dda1a6a33b14cd57e36a9755
Known-Exploited Catalog Listings
| Catalog | Added | Remediation due | Ransomware use |
|---|---|---|---|
| CISA KEV | Apr 11, 2022 | May 2, 2022 | Not reported |
| Industry KEV feed | Mar 7, 2022 | May 2, 2022 | Not reported |
| CIRCL KEV | Apr 11, 2022 | May 2, 2022 | Not reported |
| ENISA EUVD | Apr 11, 2022 | n/a | Not reported |
Required action: Apply updates per vendor instructions.
Affected Products
566 affected entries in total| Product | Affected versions | Fixed in |
|---|---|---|
| Debian LinuxDebian | 10.0, 9.0 | n/a |
| Linux KernelLinux | See advisory | 4.14.259 |
| 8300 FirmwareNetapp | See advisory | n/a |
| 8700 FirmwareNetapp | See advisory | n/a |
| A400 FirmwareNetapp | See advisory | n/a |
Patched Releases
:linux_kernel:
:2022-03-05, :2022-05-05
bpftool
5.10.46-2.ph4
cluster-md-kmp-64kb
5.3.18-150300.59.49.1
cluster-md-kmp-azure
5.3.18-150300.38.40.4
cluster-md-kmp-default
5.3.18-150300.59.49.1, 5.3.18-24.102.1
cluster-md-kmp-preempt
5.3.18-150300.59.49.1
cluster-md-kmp-rt
5.3.18-150300.76.1, 5.3.18-73.1
dlm-kmp-64kb
5.3.18-150300.59.49.1
dlm-kmp-azure
5.3.18-150300.38.40.4
dlm-kmp-default
5.3.18-150300.59.49.1, 5.3.18-24.102.1
dlm-kmp-preempt
5.3.18-150300.59.49.1
dlm-kmp-rt
5.3.18-150300.76.1, 5.3.18-73.1
dtb-al
5.3.18-150300.59.49.1
dtb-allwinner
5.3.18-150300.59.49.1
dtb-altera
5.3.18-150300.59.49.1
dtb-amd
5.3.18-150300.59.49.1
dtb-amlogic
5.3.18-150300.59.49.1
dtb-apm
5.3.18-150300.59.49.1
dtb-arm
5.3.18-150300.59.49.1
dtb-broadcom
5.3.18-150300.59.49.1
dtb-cavium
5.3.18-150300.59.49.1
dtb-exynos
5.3.18-150300.59.49.1
dtb-freescale
5.3.18-150300.59.49.1
dtb-hisilicon
5.3.18-150300.59.49.1
dtb-lg
5.3.18-150300.59.49.1
Timeline
Publicly disclosed
Jan 26, 2022
Added to Industry KEV feed
Mar 7, 2022
Added to CISA KEV
Apr 11, 2022
Added to CIRCL KEV
Apr 11, 2022
Added to ENISA EUVD
Apr 11, 2022
Last updated
Oct 14, 2026
Weakness Type
- CWE-415 Double Free
- CWE-416 Use After Free
References
- advisoryhttps://bugzilla.suse.com/1154353
- advisoryhttps://bugzilla.suse.com/1154488
- advisoryhttps://bugzilla.suse.com/1156395
- advisoryhttps://bugzilla.suse.com/1160634
- advisoryhttps://bugzilla.suse.com/1176447
FAQ
Common Questions.
A double free bug in packet_set_ring() in net/packet/af_packet.c can be exploited by a local user through crafted syscalls to escalate privileges or deny service.
Affected: Debian Linux versions 10.0, 9.0; Linux Kernel; 8300 Firmware (Netapp), among others. The full list is in the CVE brief.
It is exploited in the wild, listed in CISA KEV, Industry KEV feed, CIRCL KEV, ENISA EUVD since Mar 7, 2022.
Yes. It was added on Apr 11, 2022 with a federal remediation due date of May 2, 2022.
Public exploit code is available.
Fixed versions are available, including :linux_kernel: :2022-03-05, :linux_kernel: :2022-05-05, bpftool 5.10.46-2.ph4.
Brandefense priority: patch immediately, because it is listed as exploited in the wild.
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